Flavored foods



' markedly greater resistance Patented Dec. '22, 1942 Roland E. Kremers,Summit, N.

General Foods Corporation,

1., asaignor to New York, N. Y., a

corporation of Delaware No Drawing. Application August 3, 1989, SerialNo. 288,227

17 Claims.

This invention pertains to the preservation of aromatic or flavorcompounds, particularly in food products, so against loss ordeterioration oi flavor or aroma during the period between manufactureand actual use thereof, and is a continuation in part of my applicationSerial No. 136,667, filed April 13, 1937.

It is well known that the aroma and flavor of many articles of food aretheir most valued characteristics and are essential to their successfulmerchandising. This importance has led to the concentration and study ofaroma and flavor bearing substances, the concentrated flavor and aromabearing volatile oils of fruits or other food materials being manifestproducts of such efl'orts. With the concentration of aromas and flavorsit has been possible to add attractive and appealing Qharacteristics tootherwise odorless or flavorless materials.

With the advent of goods in package form, many articles were reduced toa sensibly dry condition for convenience and stability duringmerchandising, and the above mentioned aroma and flavor concentrateshave been incorporated into such dry products in various ways known tothe art and often by the simple expedient of thorough mixing.Unfortunately such products often deteriorate life and lose their appealbecause of theinstability of the flavor and aroma bearing chemicalconstitutents in spite of the greatest care in the design, materials andsealing of the packages. To overcome this difllculty it has sometimesbeen proposed to add synthetic substances which have a, more powerfularoma or flavor, such addition of synthetics being commonly referred toas a "fortification" of the weaker natural flavors and aromas. 'Althoughthe strength of such synthetic chemicals they do not have, except inspecial instances, to deterioration than the natural concentrates. Whatthey add in intensity is often oi'fset by their very great volatility.

It is well known that these flavor and aroma losses even of fortifiedproducts have led to many eiiorts to prevent such losses by mechanicalmeans. For instance, efforts have been made to occlude the flavors inagglomerations or granules of bulkier ingredients of the mixtures, or toretard evaporation by dissolving the flavor in high boiling substances.However, all such attempts have at best only slightly retarded the lossof flavor and aroma.

rapidly during their shelfis often very great;

as to protect such products ing substances It is characteristic of all55 these previous efforts to preserve flavor and aroma that an aggregateof fiavor bearing materials has been subiected as an entirety to thesame mechanical or physical manipulation without regard to the stabilityor instability of the individual constituents of the, aggregate.Hermetical sealing of materials in the absence of atmospheric oxygenaccomplishes the desired end for some commodities, but it introduces anunwarranted manufacturing cost and provides no protection after the sealhas once been broken.

In contrast to this prior art, it is a characteristic of the presentinvention that the preservation of flavor and aroma of food products ofthe type described above is accomplished through chemical manipulationsbased on-and adapted to the specific reactivities of individual chemicalconstituents of the flavor and aroma bearing volatile oils.

The aroma and flavor bearing substances of fruits and other foodmaterials are found principally in the volatile oils and investigationand study of these oils have shown that the most important flavor andaroma bearing constituents of these oils are aldehydes, alcohols,ketones, esters, phenols, and lactones. Broadly speaking thedeterioration of flavor and aroma in food products containing addedvolatile oils is due to changes in these constituents caused by twogeneral processes. The first process is that of volatilization, wherebythe flavor or aroma bearevaporate more or less rapidly due to theirmeasurable vapor pressure. The second process is that of oxidation. Suchsubstances may be unstable to atmospheric oxygen in a variety of ways.They may be oxidized to other compounds, or they may undergoresinification or polymerization as a result of the more orlesscatalytic eflect of lesser quantities of oxygen. An accessory factorwhich tends to accelerate these deteribrating effects of evaporation andoxidation is the common practice of spreading the added volatile oilover the surface of the dry ingredients which constitute the bulk of thefood. The rate of flavor loss is a more or less individualcharacteristic of each volatile oil constituent. In an acidulatedgelatine dessert powder, for example, the flavor and aroma ofhenzaldehyde and citral vanish or deteriorate materially in two weeks orless, whereas certain other constituents such as decanal are morepersistent. Nevertheless in virtually every case a distinct change ofaroma or flavor occurs, leading to a deteriorated product.

Protection both against evaporation and against atmospheric oxygen istherefore essential to overcome the deterioration and to avoid thewasteful and uneconomical practice of adding excessive quantities offlavor materials to allow for loss.

One of the objects of the present invention is to prevent deteriorationof the aroma and flavor of food products of the type characterized aboveby utilizing the chemical aiflnities of "the aroma and flavor bearingsubstances-to form compounds of sufllcient stability againstvolatilization and oxidation substantially to withstand change duringthe shelf-life of the product, both in the store and in the home, but ofsuch nature as to release the desired aroma or flavor during thepreparation or use of the product.

Another object is to provide a method of imparting flavor or aroma to afood product wherein flavor or aroma is released or regenerated innascent state from chemical combinations with another substance duringthe preparation of the food for consumption.

Another object is to provide a packaged food product having improvedflavor and aroma characteristics at the time of use or consumption dueto the prevention of deterioration and the release of fresh'flavortherein.

A further object is to provide a food product containing an aroma orflavor bearing substance chemically combined with an edible butsubstantially odorless and tasteless substance to form a reactionproduct that is substantially unaffected by oxidation and substantiallynon-volatile so that said product can be packaged and stored in ordinarypaper or other suitable packages without material deterioration of aromaor flavor. I

Another object is to prevent the evaporation oroxidation of individualconstituents of volatile oils added to food products of the typecharacterized above by the prior conversion of such constituents intodefinite, preferably solid chemical derivatives.

A still further object is to minimize change in the added reactionproducts during storage by using preferably solid derivatives wherebycontact with other ingredients and exposure to atmospheric conditions isgreatly reduced.

To the above ends one or more aroma or flavor bearing substances thatare desired for a given food product, and particularly those chemicalconstituents which are characteristicallypresent in natural volatileoils having the desired flavor and aroma, are first chemically combinedwith suitable reagents to form reaction products that are stable,substantially non-volatile, and substantially non-oxidizable as comparedwith the uncombined substances. Such reaction products are thereforevehicles whereby flavor and aroma bearing substances can be added tofood products which can then be kept or stored substantiallyindefinitely, or packaged in ordinary paper or other suitable cartonsand kept on the shelf without material change in or loss of saidsubstances for periods that are relatively long as compared with similarproducts as now marketed. If then the reaction product is such that theconditions of preparation or use of the food bring about the breaking upor decomposition of the reaction product, the original flavor or aromabearing substance may be liberated or regener ated in the food withouthaving undergone deterioration during the period between manufacture anduse.

The flavor and aroma bearing constituents of the natural volatile oilscan be classified on a functional basis in terms of their characteristicatomic or functional groups, such as the hydroxyl (-OH) group in thecase of the alcohols and phenols, the carbonyl (:0) group in the case ofaldehydes and ketones, etc. A reaction which involves a functionalground a compound and ble to employ any one of a number of suitablereagents provided the reaction products are stable against deteriorationand have no deleterious effect onthe flavor and aroma bearing substancesor on the food products. Since as indicated above any change in thechemical make-up of the flavor or aroma bearing substances may lead toan undesirable change or loss of flavor and aroma, the chemical reactionis preferably such that under the conditions of preparation or use theoriginal aroma or flavor bearing substance may be liberated or madeavailable in its original or unchanged form. Further the reagents usedshould be acceptable as ingredients of foodstuffs whenever the productis intended for human consumption, and should be compatible with thefood in the sense that they do not of themselves contribute anyobjectionable aroma or flavor; ii they are not odorless or tastelessthey should have characteristics which are desirable or at least notobjectionable in the food in which they are used. The term "compatiblewill be understood to have this meaning throughout this speciflcationand the appended claims.

The reaction product must also be unstable under the conditions ofultimate preparation or use of the food. The factors which may bringabout the regeneration of the original aroma and flavor bearingsubstance will vary according to the manner of preparing or using thefood and include: the mass action of water; the catalytic effect ofacids, for instance fruit acids; the conditions obtaining in the mouth;elevated temperatures, for instance the temperature of hot or I boilingwater; or other operations employed in the preparation, consumption, oruse of the food. Any reagent may be employed which complies with theforegoing requirements and provides a reaction product that issubstantially non-volatile, as compared with the original substance, andsubstantially stable to the ordinary conditions of temperature andatmosphere encountered in the marketing of the particular food in whichit is incorporated. Accordingly the normal composition, the normal stageconditions and the normal methods of preparation of any given foodproduct of the type concerned constitute conditions which determine thedegree of stability and reversibility demanded of each chemicalderivative of a volatile oil constituent to be added to said foodproduct and are in effect the specifications of the requisite propertiesof these chemical derivatives.

The invention is applicable to a wide variety of food products such ascereals, dessert preparations, jelly mixtures, beverage substances andextracts, chickle, etc. The well-kown flavored and sweetened dessertmixtures, for example, gelatin desserts, pudding powders, ice creammixes, eta, furnish convenient illustrations of the application of theinvention. mixtures is not economically practicable and they arecommonly packaged in paper containers which may remain. on the shelf forsubstantial periods before they are sold and for further substantialperiods in the home before they are actually used. The volatile andoxldizable constituents of the natural volatile oils found inconcentrated flavoring extracts-derived from fruits and other foodsdeteriorate rapidly under these conthe time that has elapsed since themanufacture of the product.

Under the functional classification referred to above, chemicalconstituents of volatile oils characterized by a carbonyl or hydroxylgroup form two important classes of flavor and aroma bearing compounds.Functional derivatives of compounds of these classes can be formedaccording to the present invention by various reactions, among which maybe mentioned reaction or use regardless of Carbom/l-amine groupreactions Benzal-dflethyl carbamate).-M. P. 181-182 C. This compoundmayreadily be made by adding 53 grams of pure benzaldehyde to 89 grams ofethyl carbamate dissolved in 165 grams of dichlorethane. To this waterbath, 12 drops of concentrated hydrochloric acid are added to catalysethe condensation; the mixture then is allowed to cool. ti hour 132 cc.of hexane are added and crystallization is completed by storage at C.crystalline product is collected by suction filtration, washed withhexane and recrystallized from 3 parts of dichlorethane.

Benzaldehyde has been used extensively in the preparation of cherryflavors, which have often been labeled "cherry pit flavors. However,benzaldehyde is notorious for its speed of oxidation when exposed toair, and if used in dessertmixtures of the type commonly merchandlzed inpaper containers, its flavor and week's time of ordinary storage byreason of its oxidation to benzoic acid. The di- (ethyl carbamate)derivative of benzaldehyde on the other hand is an odorless,crystalline,

or indirect elimination of water solution, warmed on a Hermeticalsealing of such stable solid which does not deteriorate and which in thepresence of a weak acid and warm water will liberate benzaldehyde. Inthe case of its addition to a dessert of the character mentioned, forexample, the benzaldehyde is therefore in eirect added in a fresh andunaltered condition during the preparation of the product for theEthanal-dflethul carbamate).-M. P. C. This compound may be prepared bycondensing a cooled mixture of acetaldehyde and ethyl caracld. It ispurifled by recrystallization irom water. The occurrence of .ethanal inthe cohobated aqueous distillates of numerous volatile oils indicatesits usefulness in imparting "top odors and freshness to food products,although heretofore the use of ethanal as such has been impracticalbecause of its great volatility and reactivity.

iso-Pentanal-dflethyl carbamate).-M. P. 129 0. compound may be preparedby condensing isovaleric aldehyde and ethyl carbamate with a smallHeptanal-di(ethyl carbamaieL-M. P. 116- 117 C. This compound ispreferably prealdehyde has been almost impossible because of its promptoxidation to the objectionable heptoic acid.

OctanaLdKethyl carbamate).-M. P. 114-- 1l4.5 C.

odor purity from a mixture of ethanol and water.

in lemon and lime flavors, as indicated by its natural occurrence inlemon and neroli oils.

Nonanal-dflethyl carbamate).-M. P. 112.5"- 113" C. This compound isprepared like its next lower homolog, and is useful in imparting a sweetor flowery note to citrus and other flavors. i

Decanal-dflethvl carbamate).-M. P. 111.5- ll2.5 C. This compound isprepared like the preceding two compounds, and may be used to impart afresh and natural flavor to 1 orange flavored products. Decanal is anatural constituent of oranges, but is very unstable.

Condensation products of higher aldehydes may be prepared in the mannerdescribed above and used for their characteristic flavor and aroma; asfor example undecanal-di(ethyl carbamate), M. P. 109-l09.5 C. andduodecanaldi(ethyl c'arbamate) M. P. l08-108.5.

Furjwral-di-(ethyl carbamate) .--M. P. 166- 167 0. Appropriatequantities of redistilled furfural and ethyl carbamate are warmedtogether until solution is complete. The condensation is eflected asusual by a drop of concentrated hydrochloric acid. The product ispurified by recrystallization for dilute ethanol. Furfural is acharacteristic constituent of many carbohydratecontaining products whichhave been subjected to heat, such as coffee and coffee substitutes.Furfural-di-(ethyl carbamate) is useful in preserving the aroma andflavor contributed by furfural to such products and may be incorporatedwith dried, water soluble extracts of such beverage materials. Sincesuch extracts are acidic, pH about 5.0, the addition of hot waterproduces an acid solution which regenerates-the furfural.

Benzal-di(butyl carbamate) .--M. P. 126.5-128" C. This compound may beprepared by condensing butyl carbamate with benzaldehyde in the mannerdescribed above for benzal-di(ethyl carbamate). The white crystallineproduct is purifled by washing with hexane and water. In acid media,such as 2% tartaric acid, or in acidulated gelatin desserts this productliberates the aroma of benzaldehyde but not that of butyl alcohol.

Benzal-diurei-de.--M. P. 190 C. This compound is prepared by reacting 25grams of benzaldehyde with 50 grams of urea in 50 cc. of water for 24hours. Its excellent stability and its ready regeneration by weak acidsat low temperatures make it very suitable for gelatin desserts preparedwith warm water.

BenzaZ-di(methylureide) .--M. P. 180-181 C. This compound is prepared bydissolving 1.0 cc. benzaldehyde, 1.5 grams of methylurea, and 1 drop ofconcentrated hydrochloric acid in dry alcohol and refluxing for twohours. It is obtained as a white crystalline solid by evaporating thealcohol under reduced pressure and washing out the impurities withdilute ammonia and water. It is more stable than the preceding compoundor benzal-di(ethyl carbamate) and may be i used in'food products whichrequire brief boiling, such as pectin jellies.

Ethanal-ureide.--M..P. 173-175" C. This compound is prepared by mixinggrams of urea dissolved in cc. of water with 4 cc. of 50% ethanal. After16 to 20 hours, it is obtained as a white solid which is thenpulverized, washed with water, and air dried. It is useful for impartingfreshness to a variety of fruit flavors.

NonanaZ-ureide.-M. P. l85l90 C. This compound is prepared by shaking 1cc. of nonanal with 10 grams of urea dissolved in 5 cc. of warm water.Upon cooling, partial crystallization occurs after which the magma isthoroughly mixed and set aside. The product is then filtered and washedwith water to remove excess urea and triturated' with. alcohol to removeunreacted nonanal. The compound is useful in conjunction with citrusoils.

Decanal-ureide.-M. P. 190-200 C. This compound is prepared like thepreceding compound andis similarly useful in conjunction with citrusoils.

.Dinoetyl-thioureide.-M. P. 118-ll9 C. This compound is prepared byadding 135 grams of pulverized thiourea to 300 cc. of 95% ethanolcontaining 5 drops of concentrated hydrochloric acid and mechanicallystirred. To the mixture are then slowly added 150 cc. of

.diacetyl and stirring continued until crystallization occurs. Thecompound is recovered by suction filtration, washed with 95% ethanol,washed twice with chloroform, once with ether, and then air dried andpulverized. It is primarily valuable for imparting butter orbutterscotch flavors and is also useful in connection with driedextracts of roasted beverage materials and with certain fruit flavors,such as raspberry, orange, and strawberry.

Diacetyl-di(ethanolamine).-M. P. 121-123" C.

. This compound is prepared by reacting 2.15 grams of diacetyl with 3.05grams of ethanolamine. The crystalline product obtained is washed withalcohol and air dried. It is useful for producing the same flavors asthe preceding compound, but is more sensitive to acids.

Acetylmethylcarbinol ethan0laminc.-M. P. 101-l02 C. This compound isprepared by reacting 3 grams of acetylmethylcarbinol with 2.08 grams ofethanolamine. It is a crystalline, practically odorless substance whichis very sensitive to acids and is useful in producing butter-likeflavors.

N-citrylidene-glucosamine.--M. P. 139-140 C. This compound is preparedby adding 5 cc. of dry ethanol to a mixture of 2 cc. of citral and 1.06

grams of gulcosamme with slight heating and then filtering. Aftercooling, it separates as a white crystalline substance in the reactionmixture which is thendiluted with an equal volume of dry ether andrefrigerated for 3 hours, followed by flltration and washing with ether.It is only slightly soluble in water, but readily soluble in 2% tartaricacid and is useful in imparting the lemon-like flavor of citral.

N-cztryZidene-glucose ammonia. -M. P. about 50 C. This compound isprepared by reacting citral and glucose ammonia in warm methanol. It isan amorphous, glassy substance useful in producing lemon-like flavors,but is more sensitive to acids than the preceding compound.

N-cinnamylidene-anthranilic acid.-M. P. 163- 164 C. This compound may beprepared by warming anthranilic acid and cinnamic aldehyde in a toluenesolution. It liberates cinnamic aldehyde in dilute acid and may be usedunder these conditions for its cinnamon flavor.

N-citryZidene-p-amino-sodium benzoate.--This compound may be prepared bycondensing citral with an aqueous solution of sodium-p-aminobenzoatefollowed by filtration and careful drying. It is useful with lime orlemon flavors.

N-citrylidene-sodium-glutamate.--This compound maybe prepared bycondensing an aqueous solution of sodium glutamate with citral and asuflicient quantity of ethanol to make contact. The solvent is thenevaporated and the product washed with hexane. This compound is usefulwith lime or lemon flavors.

N-benzylidene-caZcium-glycinate.-This compound is prepared by shaking10' cc. of benzaldehyde with a solution composed of 7.5 grams of glycineand 8.8 grams of crystalline calcium acetate dissolved in 40 cc. ofwater to which 10 cc. of concentrated ammonia have been added. Thecompound separates as a white crystalline sub stance and after 4 hoursof refrigeration is collected on a filter and washed with water andethanol. It is insoluble in cold water, but is slowly hydrolyzed by hotwater and dilute citric acid to liberate benzaldehyde.

N cinnam'ylidene calcium glycz'uate. This compound is prepared bydissolving 2 grams of glycine and 1.0 gram of calcium hydroxide in 5 cc.of hot water and flltering to remove excess slaked lime. The filtrate isthen shaken with 1.0 cc. of cinnamic aldehyde, and after 2 hoursrefrigeration the compound separates out and is collected on a filter,washed with water, alcohol, and ether, and then dried. It liberates thecinnamon-like flavor oi cinnainic aldehyde upon contact with diluteorganic acids or saliva and is useful in the flavoring of chicle,gelatin desserts, and other mixtures.

N-isopentylidene calcium glutamate. This compound is prepared bycondensing rectified isovaleric aldehyde with a solution of calciumglutamate. The ready regeneration of the aldehyde gives particularlyvaluable results in conjunction with volatile sulphur compounds whenadded to dried extracts of roasted beverage materials.

N jur'jim/lidene calcium glutamate. This compound is prepared in thesame manner as the preceding one and is useful in similar applications.

N-benzylidene-calcium-alutamate.--This compound is prepared in a mannersimilar to that used in preparing the corresponding glycinatederivative. It also may be obtained directly from oil of bitter almonds.It is useful in producing cherry flavors in-materials intended to bemade up with warmwater.

N-cimiamylz'dene calcium.- nlutamate.-- This compound is prepared eitherfrom isolated cinnamic aldehyde or from a volatile oil such as cassiaoil. In the instance of the latter procedure, an aqueous solution ofcalcium glutamate is agitated with an alcoholic solution of cassia oilcontaining sufllcient aldehyde to combine with the amino acid. Thecompound is isolated by separating the aldehyde derivative from thenonaldehyde constituents of the cassia oil or the reaction mixture maybe directly incorporated into a sufllcient quantity of anhydrous glucoseor other suitable desiccant capable of taking up the extraneous liquids,water and alcohol. After the mixture becomes sensibly dry, it iscomminuted and can be used very efiectively to impart a cinnamon-likeflavor to gelatin desserts and other products.

N-citrulidene-calcium-olutamate.--This compound is prepared underconditions similar to those described for the preparation of thepreceding compound. It is a nearly colorless substance which isinsoluble in water and on contact with citral. As in the two dilutecitric acid liberates preceding cases, the procedure for producing thisderivative of citral may be adapted to a variety of starting materials,including pure citral, terpeneless lemon oil,- so-called lemonconcentrates, and cold pressed lemon oil. The reaction product may beisolated and purified, or it may be further manipulated in contact withthe non-aldehydic and unreacted portions oi! the starting material. Methyl-ahthranilate-alucoside.-M. P. 157-158 C. This substance isprepared by the condensation of equal parts of glucose andanthranilicacid-methyl ester in 95% ethanol with acetic acid ascatalyst. It is useful for the grape-like flavor "which it liberates incontact with dilute acids.

N-ethylidene-methyZ-anthranilata-M. P. 125- 126 C. This compound isprepared by condensing acetaldehyde and methyl anthranilate in an ethersolution without a catalyst. It illustrates a reaction product involvingmethyl anthranilate which has a grape-like flavor and ethanol which is,a common top component or some natural fruit flavors.

The following examples illustrate functional derivatives iormed byreactions involving carbonyl and hydroxyl groups which, while withinCarbonyl-hydroxyl group reactions Benzal-a-methyl alucoside.-M.'P.166-167 C. This substance results from the interaction or benzaldehydeand a-methyl glucoside with the loss of 1 molecule of water. It isresolved again into its original components by solution in warm, diluteacids, thereby releasing the characteristic cherry flavor.

Diacetone-glucose.--M. P. 107 C. This compound is prepared by condensingits components in the presence of copper sulphate and concentratedsulphuric acid. It is useful in desserts to modify top aromas, as wellas in dry beverage extracts to replace aromatic constituents lost duringdessication.

Geranyl nemz-acetal of penta-acetyl-aldehydouaZactose.M. P. 9l-92 C.This compound is prepared by dissolving ,1 grain ofaldehydo-dgalactose-penta-acetate in 4 cc. of geraniol warmed on ahotplate. The solution is chilled in ice, diluted with 4 cc. ofalcohol-free ether and 4 cc. of hexane, and kept overnight at 5 C. Thecrystalline hemi-acetai is collected on a Hirsch funnel, washed withether and hexane, and recrystallized from geraniol. flavors.

Citronellyl hemi-acetal of penta-acetyl-aldehz/aoyalactose.M. P.102-103" C. This product is prepared by the umon oi its componentsandpurined by the technic described tor the preceding compound and like itis userul in citrus flavors.

flienylethyl hemi-aceial of penta-aeetyl-aldelwdoyalacro'sa M. P.103-104 C. This substance is prepared from its components and can beused in citrus flavors like the two preceding compounds.

Mam/wt hemi-acetal of penta-acetul-aldehydoflalactose.-M. P. 89-91 C.This compound is prepared by condensing the reactants dissolved in drybenzene with av trace of dry hydrogen chloride as catalyst. The reactionis stopped at the hemi-acetal stage by washing out the acid. It isuserul in mint flavored products and for imparting the cooling sensationof menthol.

Phenylethz Z hemi-lceral of dzmethylatloxam- M. P. -102 C. Thissubstance is prepared by combining phenylethyl alcohol withmethylailoxan in dry acetone. it is recovered by evaporation of thepecanolhemi-acetal of decanal.M. P. 31 C. This product is prepared byreacting equi-molecethanol.

protected and both It is useiul in citrus freshness" into citrus ride.It regenerates methyl mercaptan upon addition of an aqueous buffersolution of about pH 5 and isuseful in dry roasted beverage materials.

Methyl mercapto hemi-aceta'l of mute-acetylaldehydogaZactose.-M. P.1l0-ll2 C. This substance is prepared by allowing an excess of methylmercaptan to react at a temperature below C. withpenta-acetyl-aldehydogalactose dissolved in dry benzene. After a periodat room temperature, the solid reaction product is collected on a filterand washed with benzene and hexane and recrystallized from benzene. Likethe preceding compound, it readily regenerates methyl mercaptan uponaddition of a bufier solution of about pH and is useful in similarapplications.

The following illustrations exemplify functional derivatives involvinghydroxyl and carboxyl groups which, while within the scope of thepresent invention and broadly claimed herein, are specifically claimedin my companion application Serial No. 288,229. As in the case of thepreceding two groups of reactions, the flavor and aroma bearingconstituent may provide either of the functional groups involved in thereactions, or both reactants may be flavor and aroma bearing, in whichcase they both will be protected and both will be regenerated. Itfurther will be evident that whichever group is provided by the flavorand aroma bearing constituent, the reactant supplying the other groupmay be selected from a wide variety of substances.

Hydroryl-carboxyl group reactions PhenylethyZ-gZuconute.-M.P. 104-106 c.This substance is prepared by mixing 2 grams of glucono-lactone with cc.of phenylethyl alcohol and introducing a small amount of dry hydrogenchloride. The mixture is heated until the lactone is completelydissolved, and after crystallization excess liquid is removed bypressing the product on a porous plate and by prolonged contact withether. It regenerates phenylethyl alcohol slowly in acidulated gelatindesserts.

Terpinyl-potassium-carbmate-Potassium terpineolate is prepared in theusual manner and at the end of the reaction the liquid is decanted fromthe excess metal and diluted with 1 part of dry toluene and 2 parts ofdry ether. bon dioxide gas is then bubbled through the mixture untilprecipitation of the carbonate is complete, after which the product iscollected on a filter, washed with ether a'nd dried in a vacuum. Itregenerates a good. terpineol flavor and aroma in acidulated gelatindesserts and is useful with distilled lime gil flavors.

6 M enthyl potassium-carbonate. This product is prepared by the technicdescribed for the precedingcompound and is useful in producing amintyflavor or cooling sensation.

Abetylanhydrocitric acid-M. P. 125-127" C. This compound is prepared bythe reaction of cetylchloride on dry citric acid and may be purifledconveniently by recrystallization from dichlorethane. It, as well as itsderivatives, acetylcitric acid and trisodium acetylcitrate, are useful75 1s di t under Dry car in small quantities for imparting a tart noteto certain fruit flavors.

Propionylanhydrocitric acid.--M. P. 134-138 C. This product is preparedlike the preceding compound, with the substitution of propionylchloridefor acetylchloride, and its uses, as well as those of its correspondingderivatives are analogous.

Caproylanhydrocitric acid-M. P. '7578 C. This products results from thereaction of caproylchloride on citric acid. If necessary,crystallization may be induced by washing with hexane. It is useful inapplications similar to those described in connection with the twopreceding compounds.

Iii Will be understood that although the three groups of reactionsdescribed and illustrated above are of wide application and aredesirable because of their convenience and suitability, otherappropriate types of reactions may also be employed. Thus it may bedesirable with some volatile oil constituents to use inorganicreactants, such as metals, which are compatible with the food to whichthey are added, as illustrated by the following examples:

Sodium vanillinata-It is well known that because of its phenolicproperties vanillin reacts with alkali hydroxides. The sodium salt ofvanillin is a stable, crystalline, odorless solid from which vanillin isreleased by weak acids.

Sodium methyl salicyZate.-This substance is preferably prepared by theunion of the salicylate with sodium hydroxide in alcohol solution. Inaddition to being used for its Wintergreen flavor, which is released byweak acids or merely the addition of water, it may also be used to shadeother flavors.

Sodium coumarinate.-'I'his compound is prepared by reacting coumarinwith an equivalent quantity of concentrated sodium hydroxide solution.It is a crystalline, virtually inodorous solid which on contact withdilute acids liberates coumarinic acid which in turn reverts tocoumarin. It is useful in imparting the characteristic aroma and flavorof coumarin to gelatin dessert prepail'iations, roasted beveragematerials, and the 11 e.

It will be apparent that it is not essential to isolate the desiredvolatile oil constituents in pure form in order to produce functionalderivatives thereof in accordance with the present inventicn, since incertain cases the same reactions and the same derivatives will beobtained regardless of whether an individual constituent is treated inisolated form or in the presence of other constituents of the volatileoil in which it occurs. It hence will be understood that the referencesherein and in the appended claims to the treatment of individualchemical constituents of volatile oils include the formation of reactionproducts not only by treatment of isolated constituents but also byselective reaction upon such constituents in the presence of otherconstituents of the oils containing them.

It further will be apparent from the foregoing 5 description that theinvention is applicable to a wide variety of aroma and flavor bearingconstituents of volatile oils. While the speciflc reagents may vary withdifferent constituents to be stabilized and with the food to beflavored, the reactions have in common the formation of a functionalderivative of the flavor and aroma bearing constituent that issubstantially nonvolatile and non-oxidizable under conditions attendingthe marketing of the product, and which the conditions of ultimate useof the product. Thereby the flavor and aroma of the stabilized materialsare imparted to the food in a nascent state with full freshness andintensity, at the instant of preparation or use and substantiallyregardless of the elapsed time since manufacture of the food. Not onlyis deterioration prevented and a full fresh flavor obtained, but alsothe invention makes unnecessary the use of excessive quantities offlavor materials heretofore sometimes added to allow for loss. Furthersince volatilization and oxidation cease to be a factor, cheaperpackages may be used and less care in sealing required.

The foregoing illustrations are by way of example only and are not to beunderstood to comprise the limits of the invention. Other reagents andother stabilizing reactions will be apparent to those skilled in theart, in the cases both of the flavor and aroma bearing substancesexpressly referred to herein as well as others. Furthermore somevariation in the reagents used is to be expected depending on the natureof the food to which the flavor is to be added. Thus a reagent, whenregenerated, may have a taste which would be acceptable in one food butnot in another. Also in a non-acid product, for example, the reactionshould be such as to be reversible in the absence of acid. Moreover, insome cases a stable reaction product may be formed from two flavorbearing substances both of which are desirable in the product to beflavored, in which case the use of additional reagents may be avoided.These considerations which control the selection of the most suitablereagent for a particular flavor or aroma and food will readily beunderstood by those skilled in the art, in view of the above discussionof the principles involved. It will also be understood that any one or aplurality of these reaction products may be added to the same food,either comprising the entire flavor and aroma or a portion thereof orbeing used as a fortification of the natural flavor and aroma bearingsubstances. These various embodiments will be within the knowledge ofthose skilled in the art without departing from the spirit of theinvention and reference should be had to the appended claims todetermine its limits.

Although this invention is described in terms of constituents of thenatural volatile oils and although it is practiced preferably by usingnatural materials, there is obviously little, if any, chemicaldiflference in a given compound due to its origin, i. e., whethernatural or artificial. Therefore, it is regarded as within the presentinvention to substitute an artificial flavor or aroma bearing compoundfor one of natural ori-. gin or to extend a given reaction-to othercompounds of the same class when the difference involved is essentiallya question of the natural occurrence or artificial production of thearomatic compound to be protected.

Certain of the reactions and processes of preparation that are describedabove embody per se features of novelty that will be claimed in separateapplications and hence are not claimed speciflcally herein.

What is claimed is:

1. The method of imparting flavor to a food product which comprisesadding thereto a stable, substantially non-volatile, non-oxidizablefunctional derivative of a flavor or aroma bearing constituent of avolatile oil, which derivative is decomposed under conditions ofultimate use of the food to liberate said constituent and leave aresidue which is compatible with the flavor and aroma of the food.

2. The method ofimparting flavor and aroma to a food product whichcomprises adding thereto a stable, substantially non-volatile,non-oxidizable functional derivative of a flavor and aroma bearingconstituent of a volatile oil, which derivative is hydrolyzed underconditions of ultimate use of the ,food to liberate said constituent andleave a residue which is compatible with the flavor and aroma of thefood.

3. A process of imparting flavor and aroma to a food product at the timeof use which comprises adding thereto during its manufacture a stable,substantially non-volatile, non-oxidizable functional derivative formedby the chemical interaction of the functional groups of two reactantscompatible with the food, at least one of which is a flavor and aromabearing volatile oil constituent, the chemical reaction between saidgroups being reversible under conditions of ultimate use of the food toliberate said two reactants.

4. A process a food product at the time of use which comprises addingthereto during its manufacture a stable, substantially non-volatile,non-oxidizable functional derivative formed by chemical interaction of acarbonyl group of one reactant and an amine group of another reactant,said reactants being compatible with the food and at least one being aflavor and aroma bearing volatile oil constituent, the chemical reactionbetween said groups being reversible under conditions of ultimate use ofthe food to liberate said two reactants.

5. The method of imparting flavor to a'food product which comprisesadding thereto a stable, substantially non-volatile and non-oxidizablefunctional derivative of a flavor or aroma bearing constituent of avolatile oil having-a carbonyl group formed by chemical interaction andwith an acid amide compatible with the food, said derivative beinghydrolyzed under conditions of ultimate use of the food to liberate saidconstituent.

6. The method of imparting flavor to a food product which comprisesadding thereto a stable, substantially non-volatile and non-oxidizablefunctional derivative of a flavor or aroma bearing constituent of avolatile oil having a carbonyl group formed by chemical interaction andwith an amino alcohol compatible with the food, said derivative beinghydrolyzed under conditions of ultimate use of the food to liberate saidconstituent.

7. 'Ihemethod of imparting flavor to a food product which comprisesadding thereto a stable, substantially non-volatile and non-oxidizablegroup formed by chemical interaction and with an amino acid compatiblewith the food, said derivative being hydrolyzed under conditions ofultimate use of the food to liberate said constituent.

8. A method of imparting flavor and aroma to a food product whichcomprises adding thereto a stable, substantially non-volatile,non-oxidizable compound capable of decomposing under the conditions ofultimate use of the food to yield said flavor and a residue compatibletherewith, said compound being formed by the reaction C=0+H2N, whereinthe (2:0 group is supplied of imparting flavor and aroma to amidoesters, amino acids, amino acid esters and amino alcohols which isedible and compatible withthe flavor and aroma of the food.

9. A method of imparting flavor to a food product which comprises.adding thereto a stable, substantially non-volatile, non-.oxidizablecompound capable of decomposing under the conditions of ultimate use ofthe food to yield said flavor, said compound being formed by reaction ofthe C=O group of a flavor and aroma bearing volatile oil constituentwith the NHz group of a reagent selected from the group consisting ofurea, thiourea and methylurea.

10. A method of imparting flavor to a food product which comprisesadding thereto a stable, substantially non-volatile, non-oxidizablecompound capable of decomposing under the conditions ofultimate use ofthe food to yield said flavor, said compound being formed by reaction ofethyl carbamate with an aldehyde which is a flavor and aroma bearingconstituent of a volatile oil.

11. A method of imparting flavor to a food product which comprisesadding thereto a stable, substantially non-Volatile, non-oxidizablecompound capable of decomposing under the conditions of ultimate use ofthe food to yield said flavor, said compound being formed by reaction ofan amino acid with an aldehyde which is a flavor and aroma bearingconstituent of a. volatile oil. 7

12. A method of imparting flavor to a; food product which comprisesadding thereto astable, substantially non-volatile, non-oxidizablecompound capable of decomposing under the conditions of ultimate use ofthe food to yield said flavor, said compound being formed by reaction-of thiourea with diacetyl.

13. A foodstuff having at the time of consumption the characteristicaroma and flavor of a constituent of a volatile oil, said flavor andaroma being embodied in a. stable, substantially nonvolatile,non-oxidizable functional derivative of said constituent and a reactantcompatible with said flavor and aroma, which derivative decomposes underconditions of ultimate use to liberate said constituent.

14. A foodstuff having at the time of consumption the characteristicraoma and flavor of a constituent of a volatile oil, said flavor andaroma being embodied in a stable, substantially nonvolatile,non-oxidizable functional derivative formed by the chemical interactionof a carbonyl group of one reactant with an amine group of anotherreactant, one of said reactants comprising said constituent and theother being compatible with said flavor and aroma, said reaction beingreversible under conditions of ultimate use to liberate said tworeactants.

15. A foodstuff having at the time of consumption the characteristicaroma and flavor of a constituent of a volatile oil, said flavor andaroma being embodied in a stable, substantially nonvolatile,non-oxidizable functional derivative formed by chemical interaction ofthe carbonyl group of said constituent with an amino acid compatiblewith said flavor and aroma, which derivative is hydrolyzable underconditions of ultimate use to liberate said constituent.

16. A foodstufi having at the time of consumption characteristic aromaand flavor of a constituent of a volatile oil, said flavor and aromabeing embodied in a stable, substantially nonvolatile, non-oxidizablefunctional derivative formed by chemical interaction of the carbonylgroup of said constituent with an acid amide compatible with said flavorand aroma, which derivative is hydrolyzable under conditions of ultimateuse to liberate said constituent.

1'7. A foodstuff having at the time of consumption the characteristicaroma and flavor of a constituent of a volatile oil, said flavor andaroma being embodied in a stable, substantially nonvolatile,non-oxidizable function derivative formed by chemical interaction of thecarbonyl group of said constituent with an amino alcohol compatible withsaid flavor and aroma, which derivative is hydrolyzable under conditionsof ultimate use to liberate said constituents.

ROLAND E. KREMERS.

